A proliferation of computer keyboards in offices and homes has given rise to a dramatic increase in repetitive strain injuries such as nerve entrapments, tendon problems and muscle strain. Such injuries are commonly perceived as persistent aches in the forearms and wrists, or pain that may be felt from the shoulder to the fingertips. If left untreated, the soreness can escalate into full blown disability.
The present invention is directed a type of repetitive strain injury known as carpal tunnel syndrome. This refers to compression of the median nerve as a result of swelling of tendons and sheaths, or repeated bending of the wrist as normally occurs during extended use of computers. The position in which the hands and fingers are placed to use a keyboard typically keeps the associated muscles in flexion which may cause the carpal dome to slip in an anterior direction, causing shooting pain and numbness in the fingers. Wrist rests and other devices are commonly used to support the wrists when there is a pause during typing. However, such devices, while relieving stress on muscles and joints in some circumstances, do nothing to strengthen or rehabilitate the muscles and joints to avoid injury, or to rehabilitate from prior injury. Moreover, the advantageous aspects of wrist rests may depend on the manner in which the user's wrist is positioned. Misuse of a wrist rest may in fact cause more harm than good, increasing the potential for carpal tunnel injury.
In order to strengthen the muscles and joints of the hand to avoid carpal tunnel injury, it is desirable to strengthen the extensor muscles and joints to prevent those muscles from becoming overpowered by flexor muscles as well as becoming distrophied to the point that carpal tunnel syndrome may result. While various devices have been proposed which exercise the extensor muscles, such devices are not adequate to address the causes of carpal tunnel syndrome. In addition, prior devices which facilitate exercise of the extensor muscles in the fingers and wrists are not practical to allow convenient usage.